###链式比较
println("----chained_comparisons----")
b1 = 1 < 2 <= 2 < 3 == 3 > 2 >= 1 == 1 < 3 != 5
println(b1)

v(x) = (println(x); x)
println("--------")
println(v(1) < v(2) <= v(3))
println(v(1) > v(2) <= v(3))
println(v(1) < v(2) && v(2) <= v(3))
